STMicroelectronics A6727

Overview

A6727 from STMicroelectronics is a single-phase synchronous buck PWM controller with integrated high-current HS/LS gate drivers, designed for automotive DC-DC conversion. It operates from 5 V to 12 V supply, supports input as low as 1.5 V, delivers ±1% output voltage accuracy via 0.8 V internal reference, features fixed 300 kHz oscillator, and implements RDS(on)-based sensorless overcurrent protection in SO-8 package.

For engineers reviewing the A6727 datasheet, A6727 pinout, A6727 application, or A6727 equivalent, this controller is selected for compact, AEC-Q100-compliant buck regulators requiring pre-bias startup handling, FB disconnection safety, and programmable OCP without external sense resistors.

Technical Context

The A6727 implements voltage-mode control with a 15 MHz GBWP error amplifier and 8 V/µs slew rate, enabling fast transient response in automotive power rails. Its adaptive deadtime control monitors PHASE and LGATE to minimize shoot-through while supporting negative inductor current recirculation via watchdog logic.

Overcurrent protection uses low-side RDS(on) sensing with programmable threshold (50–500 mV when VCC = 5 V) or fixed –400 mV threshold when VCC > 8 V; undervoltage (0.6 V) and overvoltage (1 V) protections act on FB pin with hiccup-mode recovery and LS-latched FB disconnection response.

Key Specifications

Pinout & Package

Package: SO-8 (Small Outline, 8-pin, surface-mount). Thermal resistance junction-to-ambient: 85 °C/W on 2S2P board.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck controller applications.

Compared with MP2918 and TPS54290, the A6727 uniquely integrates both HS/LS drivers, sensorless RDS(on) OCP, LS-less startup, and FB disconnection protection in a single AEC-Q100-compliant SO-8 package - making it optimal for space-constrained, safety-critical automotive buck converters.

Availability

A6727 is available at Aetrix Electronics and suitable for automotive ADAS camera power supplies, infotainment SoC core rails, and body control module sub-regulators requiring stable component supply, AEC-Q100 qualification, and long-term lifecycle support.

Supply support for A6727 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, specializing in automotive, industrial, and power management ICs with vertical manufacturing and rigorous automotive qualification processes.

The A6727 belongs to ST's automotive-grade power controller product line, engineered specifically for robust, compact, and safe DC-DC conversion in engine control units, ADAS, and infotainment systems operating across extended temperature ranges.

FAQ

What is the minimum input voltage supported by the A6727 for power conversion?

The A6727 supports power conversion input as low as 1.5 V, enabled by its flexible architecture and integrated high-current drivers. This allows operation directly from low-voltage automotive buses or intermediate rails, provided the VCC supply remains within 4.1 V to 13.2 V and duty cycle constraints are observed per datasheet Table 5.

How does the A6727 implement overcurrent protection without a sense resistor?

The A6727 senses output current through the voltage drop across the low-side MOSFET's RDS(on) by monitoring the PHASE-to-GND voltage during LS conduction. It compares this to an internally held threshold (programmable at 5 V VCC or fixed at –400 mV above 8 V VCC), eliminating need for external sense resistors and associated power loss and PCB area.

Can the A6727 start up into a pre-biased output, and how is it achieved?

Yes - the A6727 implements LS-less startup: during soft-start, the low-side driver remains disabled until the high-side begins switching, preventing reverse current flow. If output voltage exceeds target, LS is enabled at soft-start end to discharge it safely. This avoids negative voltage spikes and load damage during cold cranking or hot-plug scenarios.

What protection features are active during device startup?

During startup, UVLO ensures operation only above 4.1 V VCC; soft-start ramps the reference over 5.1 ms; OCP is active after threshold setting completes (~6.5 ms); FB disconnection protection is always active via 100 nA bias current; OVP has top-priority activation once OCP setup finishes, while UVP activates only after soft-start completion.